Known in the art, there is the U.S. Pat. No. 4,495,644 of John R. PARKS et al, granted on Jan. 22, 1985, in which there is described an apparatus for signature verification. This apparatus uses a transducer pad in which the pressure of a stylus causes contact to be made between two resistive films. The resulting analogue voltage outputs are converted to digital form and processed under the control of a microprocessor to determine numeral parameters each representing a significant feature of the signature pattern. This apparatus comprises memory means in which is stored algorithms for identifying significant features of the signature, including upper and lower turning points of loops, points at which the pen is applied to or lifted from the paper, and lengths of segments of the signature measured as X or Y components or as resultant vectors of the path followed by the pen. These features might be segments of the signature, which may be recognized as the traces extending between a point at which the pen is applied to the paper and the subsequent point at which it is lifted off. These features are easily recognized by visual inspection of a completed signature, while there are others which can be only detected when the actual writing of the signature is monitored in real time. Such features include velocities and accelerations of the pen, which may be measured in the horizontal X direction and the vertical Y direction, or in the resultant direction of pen movement. It is also possible, when monitoring the writing of a signature in real time, to take note of the times at which distinctive features such as pen-ups, pen-downs, turning points are reached to derive appropriate weighted and normalized parameters based on these measurements. One drawback with the above described invention, resides in the fact that the way to obtain very significant features is not described in this patent.
Also known in the art, there is the U.S. Pat. No. 3,962,679 of Rudolf Succo ENGELBRECHT, granted on June 8, 1976, in which there is described a handwriting identification system comprising a handwriting speed transducer for directly generating a single analogue signal proportional to the instantaneous speed of any given handwriting, wherein said speed is a scalar magnitude independent of the direction of said given handwriting at that instant and has a quantitative value equal to: EQU .sqroot.(v.sub.x).sup.2 +(v.sub.y).sup.2,
where v.sub.x and v.sub.y are respectively the horizontal and vertical velocity vectors. One drawback with this system resides in the fact that, again, this patent does not describe how to obtain other significant features in order to allow a very efficient system for verifying a signature.
An object of the present invention is to provide an apparatus and a method for digitizing and segmenting a handwriting movement, and provide significant parameters for eventually verifying and recognizing the handwriting movement.